An enterprise customer may build a Virtual Private Network (VPN) by connecting multiple sites or users over a network from a telephony service provider. The enterprise VPN may be built using multiple types of access networks connecting the various customer sites and users to a service provider's network. The access is provided to each site over various layers of transport network protocol. For example, a VPN may use Layer 3 Internet protocol, Layer 2 protocols (e.g., frame relay/ATM PVC, Digital Subscriber Line (DSL), etc.), Layer 1 protocols (e.g., Synchronous Optical Networks (SONET), Ethernet, ATM, etc.) and a physical layer. Each transport layer is monitored by the network service provider using different alarm monitoring systems, designed for the specific layer. However, a network trouble, e.g., congestion, failure, etc., at any layer may have a common result/impact from the customer's perspective. For example, the customer may experience service degradation, or a service failure on his/her VPN connectivity. Often, the customer may not be able to determine the cause of the service degradation or failure. For example, if a service provider notifies a customer that a network trouble is detected, the customer may still be unable to determine whether or not a particular connectivity is affected by the reported network trouble. As the number of types of access networks increases, correlating the various types of alarms and presenting status to customers becomes a challenge.